Process of treating paper-pulp.



J'UDSON A. DE GEW, Oi MONTREAL, QUEBEC, CANADA.

rnocnssor TREATING PAPER-PULP.

No Drawing.

To all whom it mag concern:

Be it known that L/JUDSON A. DE CEW,

a subject of the King of Great Britain, and

' from, and also for facilitating the sizing and coloring of the paper,and the general working conditions of the paper stock on the papermaking machine. I

The paper stock may be treated either in the beating engine or prior toits employment therein, and my process consists essentially in thetreatment of the paper making fibers with a solution of sodium aluminateprior to the sizing and "coloring of the paper stock. The resultobtained is the y deposition of the alumina within the cellu- 'to thefiberslose or paper fibers by the absorption of sodiumaluminate, andalso the deposition on the surface of the fibers of colloidal alumina bythe principle of adsorption. It 's well known to those familiar withcellulose chemistry that cellulose will absorb approximately 2% of itsweight of caustic alkali. If the cellulose is treated with aluminate ofsoda, the surface of the fibers will be impregnated with alumina, whichwill be removed from the soda by dialysis 'durin the impregnatingprocess, and an ionization of the solution when diluted in the beatingengine will adhere to the surface of the fibers by adsorption.- I

The treatment of the paper stock, therefore, with sodium aluminateresults in aslightly alkaline reaction within the fibers,

the removal of any acidity that maybe present therein, and theimpregnation oi the fiber surface by alumina in the colloidal state. Notonly is a special character given y this treatment, but any solubleimpurities-associated with the fibers willbe thrown out of solution bythis treatment, or will be rendered insoluble. The result isthat thefibers andv the solution of water in which the fibers are suspended areboth prepared'forthe subsequent chemical and physical reactions whichtake'place in the Specification of Letterslatent.

colloi al alumina separated by the Patented Apr. 15, 1919.

Application filed September 25, 1917. Serial No. 193,162.

sizing and dyeing process, and thus proper efiiciency and uniformresults can be obtained in this further treatment. The amount ofmaterial used in the treatment will be approximately from &% to of thepaper stock treated, the proportlons depending upon the character of thefiber and the amount of impurities associated with them.

In carrying out my invention, T'prefer to add approximately from two to.five pounds of sodium aluminate toone thousand.

pounds of paper stock in a beating engine prior to its'sizin treatment.The material is then thoroughfi mixed by the beater. It

'will be obvious, however,that the sodium -also gives the fibers a morewater repellent character than that obtained solely from theprecipitation of the rosin soap by means of alum.

- In the'dyeing process, the paper stock which has had this preliminarytreatment will adsorb more of the dye than that which is untreated.Consequently, the cost of dyeing will be greatly reduced. In coloringwith ultramarine, the retention of this material is increased and thesubsequent destructive action of the alum solution is decreased, so thatthe coloring is obtained with less material than paper stock which hasnot been treated by this process. a

There are also mechanical advantages resulting from this treatment dueto the fact that any stickiness of the fibers is greatly reduced by thecoating of alumina deposited on them, and consequently it is possibletomake paper with less sticking on the wires and presses.

Having thus described my invention, what I claim 15:-

1. A-process which consists in treating paper making fibers with asolution of aluminate of soda and allowing the same to 'prior tothedyeing and sizing of the stock be taken up and reactwith the fibers,before said fibers are treated with rosin sizing solutions.

2. A process which consists in treatingv paper making fibers with a.solution of aluminate of soda and allowing the same to be taken up andreact with the fibers,-

. then treating-with rosin size'solutions con- 'taiiiirig paper makingfibers with a solution of aluminate of soda, and allowing the same tofree rosin. process whlch consists 1n treating be taken up and reactwith the fibers, then neutralizing any free or excess alkali and 'thenadding a solution of rosin soa containing free rosin which is eventua lycoagulated by means of sulfate of alumina.

5. A' process of mordanting paper making fibers so. that they will 'morereadily absorb certain classes of dyes and also colloidal solutions ofrosin in rosin soap which con- I my hand.

sists in treatin the paper making fibers with aweak so ution of sodiumaluminate alone until the fibers themselveshave become slightly alkalinefrom the absorption of this aluminate of soda. 5-

6. A processof increasing the aflinity of cellulose fibrous material forsolutions of rosin soap containing free rosin which conslsts -1I1obtalnlng a chemlcal reaction 'be-- tween the cellulose and sodiumaluminate before the soap is added .to the stock.

7 A processof sizing which comprises treating paper stock in a beatingengine with sodium aluminate and separately with rosin soa solutioncontaining free rosin acids in t e colloidal state.

8. A process of sizing paper stock, which comprises treating the same ina fluent condition. separately with a dilute solution containing asoluble aluminate and with a dilute solution of rosin size containingfree rosin acid, the solutions being diluted to such an extent that thefree alkali in the alum'lrosin acid in the soap solution.

In wltness whereof, I have hereunto set JUDsoN A. m CEW.

' nate solution will not 'sap onify the free

